Past research on maternal weight gain during pregnancy has focused on determinants and consequences of inadequate weight gain with concerns for the health of the infant. However, with the rising prevalence of obesity among women of childbearing ages and the high proportion of women who are gaining in excess of recommendations, a shift in research focus must occur to include consideration of the mother's long-term health status. This study's long-term goal is to identify modifiable behaviors for pregnant women that are associated with gaining weight above the recommended ranges and that result in high postpartum weight retention. This project will build upon and extend the on-going Pregnancy, Infection, and Nutrition study being conducted at the University of North Carolina. Presently, women are being recruited before 20 weeks gestation. Data collected includes biological specimens (urine, blood, vaginal cultures, and placenta) and information on sociodemographic characteristics, psychosocial indicators, health habits, all moderate and vigorous physical activity, dietary intake, previous and current medical history, and birth outcome. The proposed study will add three new components during the prenatal period (preconceptional body image assessment, dietary restraint, and pregnancy related weight gain attitudes) for approximately 1230 women and extend the data collection period into the postpartum months. A home visit at 3 and 12 months postpartum will include the collection of maternal weight and percent body fat, information on breastfeeding status, dietary intake and physical activity behaviors, measurement of psychosocial status, body image, and restrained eating. Multivariate techniques, specifically log-linear modeling, ordinary least squares regression, and general linear mixed modeling will be employed in the analysis. Focus groups during pregnancy and in-depth interviews during the postpartum period will be conducted to collect qualitative information on barriers and enhancements to physical activity, healthy eating, and weight loss during the postpartum period. These data, both the quantitative and qualitative, will be used to identify modifiable behaviors for pregnant women that are associated with gaining weight above the recommended ranges and postpartum weight retention.